Apparatus for shaping tubular blanks



Feb. 8, 1944. A. J. VOLLRATH 2,341,002

APPARATUS FOR SHAPING TUBULAR BLANKS Filed March 5, 1942 2 Sheets-Sheet 1 fivenfort Feb. 8, 1944. A. J. VOLLRATH 2,341,002

APPARATUS FOR SHAPING TUBULAR BLANKS I Filed March 5, 1942 4 Sheets-Sheet 2 Feb. 8, 1944. A. J. VOLLRATH 2,341,002

APPARATUS FOR SHAPING TUBULAR BLANKS Filed March 5, 1942 4 Sheets-Sheet 3 lilm 52.16 w im; I i

i l p 2f Feb. 8, 1944, A. J. VOLLR'ATH 2,341,002

APPARATUS FOR SHAPING TUBULAR BLANKS Filed March 5, 1942 4 Sheets-Sheet 4 5 Hin- ////A 23 dz yes Patented Feb. 8, 1944 Andr wJ- Vollrath, Sheboygan, Wis., assignor to Polar Ware. Company, a corporation of Wisconsin Application Marchfi, 1942, Serial-No.433A20 5 Claims. (01. 113 M) My invention relates more particularlyto apparatus for shaping, bymeans of -fiuid under pressure, hollow blanks, especially metal, into hollow articles of the desired shape, as for example articles having portions of larger diameter than the blank such as in-the case of teapot bodies, bowls, etc.

My objectsgenerallystated are to provide improvements in such apparatuses to the end that the I articles may be more speedily produced and be more satisfactory,-and the apparatuses will be adapted to better perform-the workfor which they are provided; he simplified in construction and positive in operation. Other and more specific. objectswill be manifest from the following description.

Referring to the accompanying drawings:

Figure 1 is a plan view ofapparatus embodying my invention, the ram, forming a part of .the apparatus, being omitted.

Figure 2 is a planview ofthe apparatus with certain of theupperparts thereof removed.

.Figure 3 is an. enlargedsectional viewv o-fthe apparatus, the sectionbeingtaken at the line 33 on Fig. 1 andviewedin the direction of the arrows, showingtheparts of the apparatus in one position.

Figure 4 is, an enlarged fragmentary sectional view ofthe portion of theapparatus shown in Fig. 2, the section being taken at the linegtf l on Fig. 2 and viewed in the direction of the arrows; and

Figures 5, 6 and 7, views like Fig. 3 and of the structure shown therein, illustrating the parts of the apparatus in certain positions occupied by them in the operation of forming an article.

The apparatus shown comprises a base 8 frOm the center of which a stationary cylindrical post 9 secured thereto, rises, the upper and lower ends of the post being of reduced diameter as represented at l and: l I, respectively, affording upper and lower annularshoulders I2 and I3, the post 9 hearing at its lower shoulder I3 against the upper central surface of the base 8.

I The shoulder I 2 forms an annular seat for a gasket I4 encirclingthe reduced portion IU of the post 3. the gasket 14 being superposed-by a cylindrical sleeve l encircling, and vertically slidable on, the reduced upper end [0 of the post and projecting above the upper end of the latter,

the outside diameter of the sleeve l5 beingthe same as the diameter of the intermediateportion I 6 of the post 9. The interior surface of the sleeve 15 at its upper endflares upwardly ,as

shownat. n andsthe, ip e cn fi a li ported at diametrically opposite points as indi-- cated at I8. A set screw. 19 carried by the sleeve l5 and extending intoalongitudinal key way 20 in the post. 9 serves to hold the. sleeve to a. straight line movern'ent and prevents accidental separation of the sleeve from the. post.

The upper. surface of .the. base .8. contains an annularrecess 2! concentric with. the post -9,,in

which..a plate 22 in the-form of an annulusis. located and vertically. movable. The plate 2;2 is guidedin its movements by headed. studs .23. (19:.

pending from. the plate 22. andslidable in openings'provided in the base ;8,.the.heads.24.of the studs being disposed in recesses; 25in thebaset. Coilsprings .26 interposed between the base 8 and the. plate 22 and located. in sockets 21 and 28.

in these twoparts, yieldinglymaintain the, plate 22 in the elevated position shown in Figs. 3 and.7 for a purpose hereinafter explained, in which position the heads 24 of the studs 23 bearv against the top walls of the sockets 25.

The apparatusalso comprises. a die-proper-ZS shown as of. general -frusto-conical form and formed of vtwo sections 39 and 3| of identical shape, each forming one-half of the die proper,

and together forming a die cavity132 correspondbars .31 and .38 secured between theirendsto the plate 22, as indicated at 39 and 40, to prevent accidental displacement of the. dieesections 30 and 3|. j

Theapparatus also comprises avertically movable female ram-4| disposedin vertical alinement with the die proper -,Z 9 when the latter isiin closed position. The ramAlwhich maybe reciprocated by anysuitab ee (not shown) contains a downwardly iacing cavity .92 eta contour adapting it to fit the contour of the die proper 29, whereby when the ram is lowered upon the, die proper it will prevent the spreading apart of the diesections 30 and' 3|, the ram in this position being; spaced from. the..p1ate 2 2, and its movement ;dcwvnwardly forcing the esmblv. rme jo th i p o er: 2 1 ma downward a ain -@1 rre sten :p i i sprin s t m y ereb a e iiha th Mi k. pr r sented at 43, from which the article is to be made is in the form of a cylinder having one end closed as shown at 44 in Figs. 3 and and it is assembled with the apparatus by sliding it at its open end over the sleeve I5 and post 9, with which the blank has a sliding fit, to the position shown in Fig. 3; the ram 4| being in raised position as shown in Fig? and the die sections 30 and 3| spread apart as shown by full lines in Fig. 1.

The blank 43 is deformed to conform it to the.

contour of the die-cavity 32 by means of fluid under pressure, preferably oil under high pressure, and Of a character'having high lubricating properties, introduced into the blank 43 between the blank and the sleeve I5. I

Provision is made for so applying the fluid by providing a passage 45 in the post 9 which opens at its lower end into a pipe 46 which would lead to a suitable supply of fluid under pressure, and at its upper end into the sleeve I5 from which it passes through the ports I8 into the blank 43 between the side wall thereof and the sleeve I5.

In the use of the apparatus the operator, having applied the blank 43 to the position therein as above explained, closes the die-proper 29 about the blank as shown in Fig. 3 and by dotted lines in Fig. 1. He then operates the ram 4| to force it downwardly first to engage and encompass the closed die sections 30 and 3| (Fig. 3) and then to' force these die sections downwardly, and with these s'ections,the plate 22, against the resistance of the springs 26 to the position shown in Fig. 5, the lower ends of the die sections in closed position closely fitting the blank. In this movement of the ram 4| the top wall 41 of the die-cavity 32, which in the normal position of the parts is spaced from the closed end 44 of the blank, is forced downwardly against the closed end of the blank and this downward force is exerted on the sleeve I5 moving it downwardly thereby compressing the gasket I4 between the shoulder I2 and the sleeve I5, causing the gasket to expand laterally and produce a tight joint between the gasket and the side wall of the blank to seal this joint against leakage therethrough of the actuating fluid to be applied for deforming the blank.

The operator thereupon introduces the fluid under pressure into the blank 43 through the course as above described, which deforms the blank into the shape shown in Fig. 6, the article thus deformed to the desired shape being indicated at 48. He then closes the fluid course to the source of supply, raises the ram 4| as shown in Fig. 7 andswings the die-sections 30 and 3| to spread condition as shown by full lines in Fig. 1 to permit the formed article to be removed from the apparatus.

The initial upward movement of the ram 4| permits the springs 26 to return the die-proper 29 and the plate 22 to the normal raised position (Fig. '7) which slides the formed article 48 on the post 9 and sleeve I5 to the elevation shown in this figure, in which position the lower end of the article only partially overlaps the gasket I4, permitting the article to be lifted clear of the sleeve I5 after the die sections 39 and 3| have been swung to open position.

To properly conduct the spent fluid from the apparatus an annular opening 49 is provided around the post 9 which opens into the recess 2| in the base 8, the recess 2| being provided with an annular series of radial passages 50 opening at opposite ends, respectively, into the recess 2| and into an annular gutter 5| provided on the base 8 and having a discharge pipe 52.

' formed of gage stainless steel, the gasket I4 The gasket I4 may be made of any suitable material adapted, under the pressure exerted by the ram 4|, to distort sufilciently into engagement with the side wall of the blank 43 to form a joint therewith sufficiently tight to hold the high pressure of the fluid used for deforming the blank.

By way of example it has been found that where an article is to be formed of the shape shown, which forms a tea-pot body, utilizing a blank 43 of 2 inches external diameter and may be formed of-rubber of such resiliency as to have a Durometer reading of about 70, the gasket, by way of example, being normally (Fig. 3) of 2%; inches outside diameter and approximately inch thick and of approximately /2 inch crosssectional width and in the compressing operation being compressed from about inch to 1 6 inch, the pressure of the fluid supplied for shaping the blank being approximately 5900 lbs. per sq. inch and the pressure exerted by the ram 4| bein from about 400 to 600 lbs. per square inch.

Under some conditions it may be desirable or necessary to perform the article-shaping operation by successive steps in the application of the fluid under pressure, increasing the pressure for each subsequent step, the partially deformed blank being removed and annealed prior to each subsequent step to permit of the better drawing of the blank. In the case of the particular example above given it has been found desirable to apply the fluid under pressure by a two-step operation with an intermediate annealing operation, the pressure of the fluid used in the flrst step of the operation being, by way of example, about 3000 lbs. per square inch and in the second step of the operation being, by way of. example, about 5900 lbs. per square inch.

As will be understood from the foregoing the lower end of the blank is free to slide upwardly on the post in the deforming of the blank into the die-cavity, which is of decided practical value as thereby such thinning of the metal of the blank as would occur if both ends of the blank were held in fixed position, is avoided.

While I have illustrated and described a particular construction embodying my invention I do not wish to be understood as intending to limit it thereto, as the same may be variously modified and altered and the invention embodied in other forms of structure without departing from the spirit of my invention.

What I claim as new and desire to secure by Letters Patent, is: I

1. Article-shaping apparatus comprising a member having a seat for a gasket, a gasket on said seat, a sectional die member having a diec avity for shaping a tubular blank surrounding said first-named member and gasket, a sleeve slidable on said first-named member against said gasket for forcing said gasket against said blank and means for subjecting the interior of the blank to fluid under pressure for expanding said blank into said die-cavity.

2. Article-shaping apparatus comprising a member having a seat for a gasket, a gasket on said seat, a. sectional die member having a die cavity for shaping a. tubular blank surrounding said first-named member and gasket, a sleeve slidable on said first-named member against said gasket for forcing said gasket against said blank, said members being relatively movable and said die member having a portion which, in the relaagainst said gasket, and means for subjecting the interior of the blank to fluid under pressure for expanding said blank into said die-cavity.

3. Article-shaping apparatus comprising a member having a seat for a gasket, a gasket on said seat, a sectional die member having a die cavity for shaping a tubular blank surrounding said first-named member and gasket, a sleeve slidable on said first-named member against said gasket for forcing said gasket against said blank, said members being relatively movable and said die member having a portion which, in the relative movement of said members, forces said sleeve against said gasket, means for subjecting the interior of the blank to fluid under pressure for expanding said blank into said die-cavity, and means yieldingly resisting relative movement of said members in the gasket-expanding operation. 4. Article-shaping apparatus comprising a member having a seat for a gasket, a gasket on said seat, a sectional die member having a diecavity for shaping a tubular blank surrounding said first-named member and gasket, a sleeve having its Wall ported, slidable on said firstnamed member against said gasket for forcing said gasket against said blank, and means for subjecting the interior of the blank to fluid under pressure for expanding said blank into said diecavity and entering said blank through the ported wall of said sleeve.

4 5. Article-shaping apparatus comprising a member having a seat for a gasket, a gasket on said seat, a sectional die member having a die cavity for shaping a tubular blank surrounding said first-named member and gasket, said blank having a portion at one end extending crosswise of said blank, a sleeve slidable on said first-named member against said gasket for forcing said gasket against the side wall of said blank, said members being relatively movable and said diemember having a portion which, in the relative movement of said members, engages said portion of said blank which laps an end of the sleeve and forces said sleeve against said gasket and means for subjecting the interior of the blank to fluid under pressure for expanding said blank into said die-cavity.

ANDREW J. VOLLRATH. 

